Iroet-frame upright pianoforte



S. P. BROOKS.

PIANO.

UNITED STATES PATENT OFFICE.

STEPHEN P. BROOKS, OF BOSTON, MASSACHUSETTS.

IRON-FRAME UPRIG-I-IT PIANOFORTE.

Specification of Letters Patent No. 10,770, dated April 11, 1854.

To all whom it may concern 4 Be it known that I, STEPHEN P. BROOKS, of Boston, in the county of Suffolk and State of Massachusetts, haveinvented certain new and useful Improvements in Pianofortes; and I do hereby declare that the following description, taken in connection with the accompanying drawings, hereinafter referred to forms a full and exact specification of the same, wherein I have set forth the nature and principle of my said improvements, by which my invention may be distinguished from others of a similar class, together with such parts as I claim and desire to have secured to me by Letters Patent.

The figures of the accompanying plate of drawings, represent my improvements.

Figure l is a front elevation of my piano. Fig. 2 is a central vertical section of the same.

The object of my invention is to improve the tone o-f the piano by arranging the strings upon an iron frame, with the sounding board directly attached to said frame, without the use of a wooden bed or frame as heretofore used, or of any other substance between the sounding board and the iron frame, thereby diminishing the cost of the construction of the piano, and also to improve the tone of the upright piano, by giving the blow of the hammer upon the strings in a direction from the sounding board instead of toward it, as heretofore done, and at the same time, so to simplify and arrange the action in an upright piano, as to bring it level with or below the keys so as to avoid the necessity of casing the top, thereby very materially lessening the expense of the instrument.

In my improved upright piano, the iron frame extends the whole height o-f the instrument, and is arched or curved at the top, so that it cannot be broken or sprung by the strain of the strings. This iron frame furnishes the legs and entire framework of the instrument, requiring only the strings and the action to secure as good a tone as that af forded by other pianos as ordinarily constructed. The casing can be made of any desirable shape.

a a a in the drawings represents the outer frame or casing which extends only around that portion of the piano which is below the ke s.

b b is the iron frame. The top of this iron frame is formed on the arc of a circle,

which shape gives it the necessary strength to resist the strain of the wires. l

c, c, &c., are the strings, which are arranged diagonally from the top to the bottom of the frame b b b, as shown in the drawings, passing through the bridge Z d, which is also of iron, to the wrest pins e, e &c.

j j is the sounding board attached directly to the iron panel f, f, are the keys which operate the action, placed below the said keys, by means of the rod g as follows: To the cross framing 7L. is fastened a block z', Fig. 2, to which is attached the triangular piece le 7c, with its center cut out, turning on a fulcrum at Z. This piece 7c 7c is connected to the key by the rod g, and by a pivot joint to the arm m of the hammer n (turning on a pivot at o) by the rod 77, which loosely embraces one side of the piece 7c 7:, as shown in Fig. 2. It will be seen that when the key is depressed, the rod g will lift the triangular piece 7c 7c, which will, through the rod 29, cause the hammer to strike the string. The lifting of the triangular piece 7c 7c allows the end of the rod p, which embraces it, to fall and thereby the hammer is allowed to fall back only a short distance from the strings after the stroke is given, and is caught, so as to prevent its striking the string again, before the key is depressed a second time, by the rod 29, which is caught and held by the notch g in the triangular piece thus holding the hammer near` the string, so as to give facility in repeating a note.l As soon as the pressure upon the key is removed, the triangular piece 7c k drops into its original position, ready for another blow, the rod p, being guided back to its first position at the top of the piece c k, as shown in Fig. 2, by its abutting against the rest 7'. Thus the notch Q in the piece 7c 7c, serves the purpose of a back catch, which has heretofore been commonly used for holding the hammer after the blow upon the strings.

The sounding board j j is attached directly to the iron frame, instead of being placed, as heretofore, on a wooden bed or framing, which bed required considerable expense and trouble in its construction. By thus placing the sounding board upon the iron frame, as much solidity is given to the scunding board as that afforded by an eX- pensive wooden bed.

From the above description, it will be seen that as the whole of the action is placed below the level of the keys, the necessity of casing the portion above the keys, and the expense attendant upon the same, is avoided, while the action is so simple and consists of so few parts, as to require but little eX- pense in its construction, and will be less liable to get out of order, than that commonly used in upright pianos.

ln order to cover the strings and also add to the appearance of the instrument, the portion above the keys, may, if desirable, be screened with a curtain of silk.

Having thus described my improvements, I shall state my claims as follows.

l. Placing the whole of the action level STEPHEN P. BROOKS.

Witnesses:

JOSEPH GAVETT, Esiti LINCOLN. 

